ABSTRACT Access to Home- and Community-based Long-Term Care for Persons with Dementia Dementia is the most expensive condition in the U.S. and the vast majority of costs are attributable to long- term services and supports (LTSS). Over the past 20 years, Medicaid has been working to reduce costs of LTSS through rebalancing efforts that transition individuals from institutions to home- and community-based services (HCBS). This is particularly relevant for persons with dementia who are more likely to be institutionalized, compared to persons with other chronic conditions. Yet, it is unclear whether nation-wide rebalancing efforts translate into more HCBS access for persons with dementia, and whether access to HCBS results in lower rates of institutionalization and better health outcomes for persons with dementia. It is also unknown whether any positive effects of increased HCBS access on health are equal for individuals who are racial/ethnic minorities or live in rural areas. Our mixed-methods study addresses these gaps by building on the parent grant, which examines the effects of a recent rebalancing program in the 38 states that were eligible, on the health of Medicaid-eligible individuals 18 and older. Specifically, this supplement expands our analyses to HCBS access for all states, examines Medicaid-Medicare older adults 55 and older, and compares those with diagnosed dementia versus older adults with LTSS needs but without dementia. Qualitative analyses will interview dementia patient advocates, providers, and state Medicaid administrators to assess barriers and facilitators of accessing HCBS, dementia family caregiver needs for HCBS, and how families interface with HCBS based on their economic situation, family structure, dementia-specific symptoms, and stages of dementia. Quantitative analyses will, for the first time, develop county-level measures of access to HCBS across the U.S. and test how these are longitudinally associated with self-rated health, functional limitations, long- term institutionalization, and mortality in the nationally-representative Medicare Current Beneficiary Survey (MCBS). We will compare how HCBS access differs for persons with dementia vs. persons without dementia and identify any racial/ethnic and rural/urban differences in the extent to which HCBS access influences health. The efficiencies gained through this supplement are significant since our parent grant has already completed qualitative analyses to understand barriers to HCBS generally, and obtained MCBS survey panel data that are sufficiently powered and cover a long enough timeframe (2008-2016) to facilitate longitudinal examination of racial/ethnic and urban/rural differences in HCBS access for persons with dementia. This research is innovative in its focus on more local, county-level measures of HCBS access, nationally- representative sample, mixed-methods approach to understanding HCBS needs across the stages of dementia, and examination of two sources of disparities. These findings can inform policy decisions to better serve persons with dementia who wish to remain in their homes and communities, and reduce inequalities therein.